Nanoparticles provide opportunities for technological advancement in various fields including, for example, propellants and energetics, composite structures, pharmaceuticals, and cosmetics. The acceptance and use of nanometric materials in at least some of these industries has to date, however, been generally limited as the extremely small sizes of these materials can present significant challenges in areas such as handling, dispersion, safety, and ultimate strength.
For example, while nanoparticles have shown promise for use in composite propellants, such as to significantly increase performance by altering the fundamental combustion process, their more widespread use or acceptance has been generally precluded by their tendency to agglomerate and their high surface area, which tend to limit the usefulness of the particles and the rheology of the propellant, respectively.
Further, with regard to energetic materials, besides propellants, there is a need and a desire to mitigate the occurrence of ignition of explosives which may occur due to “hot spot” formation inside the energetic crystals. Thus, there remains a need for processes or methods as well as specific materials or compositions that allow or permit the successful use and/or incorporation of nanoparticles in such applications.
Further, there has been increasing interest in the use of nanoparticles in applications such as in both pigments such as for cosmetic makeup and in efficient delivery for various medicines.
The possible biological impacts of the use of nanoparticles have, however, also become a growing cause for possible concern. For example, due to their extremely small size, the possible interaction between such particles and cell functioning can be of concern, as such interaction may interrupt vital processes.
Nanomaterials have also long been posited to enable extremely high strength composite materials, yet few (if any) of such high strength composite materials have ever been created or made in a lab environment.
U.S. Pat. No. 3,685,163 described a process where ultra-fine crystals of pure ammonium perchlorate (AP) salt were prepared in a solution of water, n-heptane, and carboxylterminated polybutadiene prepolymer. This mixture was frozen, and the solvent sublimed from the blend to leave ultra-fine crystals.